Is it true that fat people have a slow metabolic rate?
No. The heavier you are, the higher your metabolic rate, because a heavy body uses more energy and produces an increase in dietary thermogenesis (the energy required for the digestion of food and the absorption and transportation of nutrients).
Will crash dieting slow down my metabolism?
Very low-calorie diets tend to make you lose a high proportion of muscle as well as fat, and muscle increases your metabolic rate, so it may affect your metabolism. Losing weight steadily means you lose proportionately more fat, which is why it's best.
Have years of yo-yo dieting damaged my health?
Possibly. An overview of all the diet studies conducted by the University Of California, US, found that yo-yoing is linked to cardiovascular disease, stroke, diabetes and altered immune function. Also, a recent study showed it may reduce 'good' HDL cholesterol and raise 'bad' LDL cholesterol, and so increase the risk of heart disease. Yo-yo dieters may also have nutrient deficiencies. However, if you're now a healthy weight and take regular muscle-building exercise, you can improve cholesterol levels, nutrient profiles and even bone density.
Why do I never lose weight even though I eat very little?
There are several possible reasons. Firstly you may already be a healthy weight and so will find it harder to be even slimmer. If you're overweight, however, it could be that your metabolic rate is quite low because you have little muscle. Or you may be taking in more calories than you think. Studies show that slimmers tend to underestimate calorie intake by 12% to 25%.
I've given up smoking - is weight gain inevitable?
Some people do gain weight when they give up smoking, probably due to a slowing of the metabolic rate and an increase in appetite. However, most people give up smoking because they want a healthier lifestyle and, once your lungs are free of tobacco pollution, you're more likely to enjoy exercise. Ex-smokers can - and often do - reset their metabolism through exercise.
Can I spot-reduce my hips and thighs by dieting?
No, unfortunately not. Fat on the lower half of your body is hardest to get rid of - it's thought this evolved so females had enough fat stores to cope with breastfeeding and pregnancy. Better to concentrate on toning your hips, thighs and bottom with exercise.
I can never stick to a diet for long - any tips?
It helps to think about the reasons you want to lose weight. Then set a sensible target weight and a reasonable calorie intake so you're not always hungry. You might find the support of a slimming club helpful and, remember, the more activity you do, the more you can eat and still lose weight.
I get hungrier when I exercise, so there's no point, right?
Exercise doesn't automatically increase appetite - if you're hungry after a workout it's probably time to eat anyway or it's a psychological need. One study showed people overestimate how many calories they burn at the gym and eat more calories to reward themselves. If you do feel hungry, have a large drink of water to avoid dehydration, which can make you feel hungry. Then eat a small carbohydrate-rich snack, such as a slice of wholemeal bread or a banana, which will restore your blood-sugar levels.
Questions extracted from The Diet Bible by Judith Wills (Quadrille, £12.99).
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